Bittersweet Sundown
by Katastrophi
Summary: When something goes horribly wrong in the lab, likely to be John's fault, Dave is mutated into a troll. It really rubs Karkat the wrong… and right ways. troll!Dave, oral, nsfw.


co-written with TheMutantHonk

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Glancing around, the newly gray boy almost wanted to clap his hands together. "Ya know Karkitty, I see why that vampire chick bonin' Rose digs fashion so much. I look hella rad in my threads, bro. Like when you get a spiked collar for some beast of a dog and it looks sick as fuck." Dave glanced down at his red sleeve and how the color seemed to pop against the skin. His eyes fixated on Karkat, who looked like he could honestly bite a nail in half.

The nubby-horned troll in question clenched his jaws angrily, feeling his sharp teeth gnash together. A small part of him honestly wished he could use those razor-like teeth and the deadly claws on the fingers he flexed irritably to not-so-surgically remove the new troll's talking cords. Instead he restrained himself, if only for the fact that Dave was now bigger and possibly deadlier than him. So he simply resorted to wishing ill upon him and John. "Strider, just get away from me. Please. I need you here and talking to be a thing that is not happening /now/." He growled that last part, hoping to send the message across better.

Dave gave a miniscule frown, noticing his ironic facade was quite a bit harder to pull off when working with a mouth full of fangs. He licked over his teeth and pushed his glasses on his nose. Karkat sure was being a rude asshole. Wasn't he supposedly nicer to the trolls or something? "Nah, Kark. You gotta be showing me how to troll." Dave couldn't stop the slight snickering that fell from his lips.

Karkat gave a slight growl, looking up from his computer only to glare at the Gamzee-esque horns that grew from the Strider's now-even-thicker skull in the wrong fucking direction. "I'm not the only troll here, asshole. Go ask Kanaya." He hunched back over his computer, doing fuckall of nothing but pretending to be doing something more important than the shit demanding his attention now. He couldn't help his curiosity, however, and unhunched his shoulders just a touch. "Not that I care about your shit blood or really anything about you, but – just for curi-fucking-osity's sake... What the fuck are you?"

Dave sucked his teeth slightly before answering. "Oh shit, yeah. You different species have all kinds of different blood. I just assumed it was all still red, then I could be just like my bestest friend ever, Karkitty." He gave a slight purr and sat down beside of Karkat, not even bothering to look at his screen. The now black haired boy wrapped his arms around Karkat, honestly just trying to get under his skin like usual, but... wow, the little crab actually smelled quite amazing. He gently sniffed at Karkat's neck, his purr growing louder. "How do ya find out a blood color without makin' a person bleed?"

The larger troll surprised Karkat with the heavy arm tossed over his smaller set of shoulders. Dave's purring filled his ears and it did nothing but annoy him. "Oh for god's sake Strider!" He threw the arm off his shoulders and spun to face the former human. "Have you never listened to a word any of us ever fucking spoonfed you?" He gripped the former blond's head by the right horn (purely out of petty spite) and angled his head to force his head down, using his dominant (stupid mutant) right hand to snatch the shades clean from his face before the Strider could protest. His mouth was open, prepared to schoolfeed the ignorant creature in what the fuck he was when his whole body stopped short. Green. Fucking lime green.

A rather squeaky moan left Dave's lips in surprise and he whined, looking up at Karkat. The warm hand on his horn actually felt really fucking amazing. H e shifted his thighs awkwardly before remembering, oh yeah. He doesn't have a dick anymore. A tentacle had to be at least a little bit of fun, right? The newly become troll felt his cheeks flush just slightly. "Why ya gettin' your stare on so hard? You look like you're looking at some kind of alien or something."

Karkat barely registered the moan Dave elicited nor the stupid comment. His lip curled up. "Of fucking course," he finally spoke, letting go of the horn and dropping the shades into Dave's lap. "Its only fucking natural that the universe continue to take a shit on me like this." He sighed and turned away from Dave, getting up to leave. To where, he wasn't sure, anywhere but where he currently was. "Not that it means shit to you, you uncultured shit sponge, but you're a fucking limeblood."

Dave blinked several times, his face breaking it's facade. Was Karkat genuinely fucking upset? Since when did he ever just get up and walk away? The human-turned-troll grabbed at Karkat's wrist, wary of his strength and claws. "What does that mean? How does THAT manage to piss you off more than anything?" Dave swallowed thickly, deciding that had been the wrong wording. "Uh, explain what a limeblood is?"

Karkat narrowed his eyes at the apparent limeblood. He'd just been about to oh-so-eloquently tell him to fuck off, but he couldn't deny that Dave had at least had the pan to rephrase his stupid question. He glared at the hand on his wrist, though he made no move to free himself. "Limebloods are extinct, Dave." He barely noticed his slip-up, rarely (never) using Dave's first name. "They were harvested to make the sopor we sleep - slept in. We wiped them out." He said all of this in near monotone, his face falling into a blank expression.

Dave's face fell. That definitely wasn't the answer the bright eyed male had expected. He licked the color of his bottom lip before chewing the skin slightly. This was really bothering Karkat, and he couldn't figure out why. If he was okay with sleeping in practical blood then... Dave glanced over Karkat' s face, his usually angry red eyes rather downcast, openly sad. "Karkat...what... what color would your blood be if you weren't...uh...different?"

Karkat's entire body tensed up before he began to pull at his arm, trying to tug away from Dave's grip. "I'm not fucking answering that," he snarled, straining to keep his emotions under control. "Just let me go Dave, please..." How the hell had he figured it out so quickly?!

Dave's grip loosened but he didn't completely stop touching the small male in front of him. The way Karkat had reacted pretty much confirmed what he had assumed. He didn't know what to say, but he had the overwhelming urge to just hold and make the little troll feel better. The limeblood gently tugged Karkat into a hug, silently petting his back.

The redblood stiffened up once more, taken completely off guard by the sudden...comfort. "I don't need your fucking hugs, Strider," he mumbled against the larger troll's shoulder, but made no move to pull away. His body shuddered as he inhaled, and he swallowed hard, refusing to let his we eyes get any wetter. "Fuck off." His voice was thick, wavery, and if there was room to hate himself for it, he would.

Dave made a face over Karkat's shoulder. It didn't take a genius to know that the little one was upset and breaking down. He held Karkat tighter, purring gently. He wasn't sure what to do. How did trolls comfort each other? He gently nuzzled his jaw against the nubby horns on top of Karkat's head. "I don' t know how ta make this better. But..." he swallowed thickly, going against everything he'd built up to this point. "Why does it really matter that you're red rather than green? You're pretty motherfuckin' great no matter what. It's pretty cool, honestly."

Karkat scoffed at Dave's so...kind words. He wasn't too sure about how to accept them, but he supposed the idiot had a point. "I guess it doesn't matter anymore anyway," he grumbled, a small content purr rising from his chest. "They're all fucking dead now." He let his shoulders slump in defeat and reluctantly hugged Dave back, praying he wouldn't regret accepting the small comfort.

Dave was shocked to actually get any return affection from the grouchy mutant blood. He tightened his hold on Karkat's back before a very sweet smell wafted over the two them. It had almost left the Knight of Time in tears as he tried to keep his laughter down. "Your horns... bro, they smell like candy corn." He reached up a little bit, running his fingers over the smooth mound of horn on top of his little friend's head. "Do they taste like it?" Before Karkat could give him an answer, Dave leaned in, taking a smooth lick against the other. It did. He kept at it, a slight giggle on his lips as the former blond took the horn in his mouth.

Karkat's eyes widened with the warm wetness that suddenly enveloped his small, over-sensitive keratin. He opened his mouth, intent upon snarling and yelling at the stupid limeblood, but all that left his lips was a low needy mewl. The sensations shot straight to his nook and he held on to Dave tightly for fear of his legs giving out beneath him.

Dave stopped and pulled back at the sounds Karkat was making. It made his groin feel kind of...wet. This was definitely someone he wasn't used to. The light flushing on Karkat's cheeks was one of the cutest things the Texan had ever seen though. He watched Karkat's expression, his voice dropping slightly. "Did...did you like that?"

The cherryblood kept a tight grip on Dave, still wary of falling over. "Stupid shitstain;" he murmured breathily. "Our horns are fucking sensitive, you dumbshit." He licked his lips and closed his eyes, still not quite over the sensations. "...Either get the fuck out of my sight, or do it again, /now/," he growled, looking up at him with near hazy, cherry red eyes.

Dave held and gentle smirk and smiled. "I think I could manage that." He slowly lapped at Karkat's candy corn nubs and hummed, loving the way it tasted a long with the needy grips and noises slipping from his fellow Knight's lips.

Karkat's nook throbbed and he groaned, letting his eyes fall closed. He didn't bother to suppress the sounds that escaped, and butted his head upward, trying to get Dave to take more into his mouth. His face began to turn the lightest pink as he felt his bulge begin to slip from its sheath, but he barely even tried to keep it in.

Dave could feel Karkat press against him. He could feel the wriggling between Karkat's thighs and his face flushed a vibrant green color. The taller male pulled back just a bit, suddenly realizing what it was. It made Dave flush that much more, his own groin throbbing. Troll anatomy was definitely strange to get used to. He most certainly /wanted/ to get used to it though. The new-troll pressed his lips to Karkat's, hoping this was was typical custom for them. The Strider really did enjoy kissing.

Karkat devoured the lime's lips greedily, sucking on the soft flesh before lapping his tongue against those sharp teeth of his. He whined quietly, pressing his hips flush against Dave, his nook dripping warm fluids down his thighs. He dared ventured a hand upward, hesitantly running fingers along the strangely smooth keratin.

Dave's hips bucked at the contact with his horns. He could feel a tugging and almost flushing release as something seemed to push from his groin. Easily, it was the weirdest sensation he could ever describe and he had just been transmuted into a totally different species. The tentacle between his legs writhed against the material of his pants and it almost made him whine. "F-fuck," he stuttered, breaking his own mental character. The limeblood didn't quit e understand how this was going to work, never having been this close to troll sex before.

The sight of Dave's cool kid persona breaking made Karkat all the more needy and he squeezed the horn in his hand, using it to deepen their kiss. His other hand dropped to the Texan's waist, gripping his hip and fingering the waist of his pants.

Dave huffed through his nose, the writhing sensation rolling and flooding his senses. The smaller male was far more bold than he would have imagined, but Dave was fairly thankful for it. He kissed and as gently as possible nipped the mutant blood's neck. "Mhn, how... how do we...?"

Karkat gave a small mewl and panted heavily, his eyes fluttering closed only to snap open again at the stupid question. "Are you fucking serious?" He took a breath in preparation for a speech on how fucking stupid Dave was when he realized... "Uh... how do humans do it?" he mumbled dumbly, feeling pretty stupid himself.

"Well uh..." the limeblood was practically glowing thanks to blushing so hard. "Well uh... two guys have sex by one..." he fumbled, unsure of how to word it, "sticking his dick up the other one's ass...and it feels good...?" He reached down and grasped at Karkat's bum. The troll-virgin hadn't had a chance to see what they were really working with but he'd be damned if this tentacle thing between his legs wasn't going inside of Karkat.

Karkat's face burned, clearly broadcasting his mutant red. "You mean they - you guys just shove your weird human bulges up each other's waste chutes?" He looked disgusted. The waste chute was a horribly taboo thing for trolls, and was only touched upon in the raunchiest of pailing movies. "Why the fuck don't you use your nooks?"

Dave blinked, "humans don't have weird looking bulges! My cock was beautiful and very well taken care of, thank you very much." he made a face, mildly of fended. The former blond hadn't even made hentai jokes yet. "And uh...what exactly is a nook?"

Karkat's eyes widened. "You mean humans don't have nooks?" Without waiting for an answer, he tugged at the fresh new trolls waistband and tugged his god tier pants down as he dropped to his knees. His hands reached up, gently parting Dave's thighs, and one hand ventured up, slowly dipping a finger into the slick dripping nook behind his coiling bulge. "This is a nook."

Dave's breath hitched and his insides tightened. He could feel his knees warble. If this was what it felt like when a girl got fingered, holy shit. He definitely did not give enough credit to foreplay. The limeblood shuddered. "N-no, humans only h-have one or the other," his hips arched, trying to get more of that finger inside of himself.

Karkat smirked; despite how fucking weird the new information was to him, he suddenly couldn't be bothered to care less. Not as long as he had Dave /literally/ wrapped around his finger. He curled said finger, careful of his claws, and slipped a second inside, the motion all too easy with the steady drops of lime gathering into the palm of his hand. However... he was more interested in the bulge that was trying to wrap its way around his busy wrist, and, eyes set on Dave's face, he leaned forward, giving a hesitant lick from the base on his sheath to about midway up where it began to coil.

Dave bit back a whimper and took a sharp breath. He found himself threading his fingers into Karkat's hair, tugging slightly. He rolled his hips slightly , the pool of genetic material making his thighs slick. It was an awkward feeling for him but he'd be damned if he didn't enjoy it. "Fuck, s-suck it, please,"

Karkat growled low in his chest, glaring up at Dave. "The fuck does it look like I'm about to do, fucksuck?" He darted his mouth forward and nipped Dave's hip lightly in spite before he brought his attention back to the lime tentacle, putting his lips over it and sucking the tip, using the suction to pull it halfway into his mouth.

"We-well shit, you were taking long enough," the former blond hissed and his eyes closed, too focused on enjoying the actual sensations to really be any more than thrilled. Dave gently tugged at Karkat's hair and licked his bottom lip, gripping the edge of the table for support. Karkat was finally being mouthy in all of the right ways.

The mutant closed his eyes, focusing on the bulge in his mouth and the heat around his fingers. He didn't want to let on to Dave that he really kinda had no idea what he was doing, but that was definitely the case. He knew /what/ to do, of course. It was just the how part he was unfamiliar with. So he let the grip in his hair guide him as he made experimental movements with his tongue, all the while moving those fingers around inside the sopping nook he was also playing with.

The limeblood felt his insides clenching around Karkat's fingers and he blew air through his nose, trying to stay as composed as possible. Dave shifted his hips to gently rock on Karkat's fingers, an almost familiar slick heat feeling his stomach. He spared a glance down at the male on his new alien dick and gasped at the sight of the cherry red stain on his jeans. Fuck, that was kind of hot.

Karkat took a deep breath in through his nose and moved his head forward, nervously taking the lime bulge to the very back of his mouth. He swallowed hesitantly before taking the whole thing, feeling the tentacle slide into his throat. He gagged a bit, mostly from the strange sensation, but as his throat contracted he learned how to relax it and managed to swallow the squirming shaft. The act, the feeling of the bulge in his mouth aroused him more and he felt his own bulge squirm against his thighs and his nook dripped steadily. He almost wished it were his own nook his fingers were in.

Dave's legs were shaking and a very unmanly whimper left his lips. The little mutant was rather talented with that throat of his. Must have adequate practice with all of his shouting. "F-fuck bro," he whined and gripped at the table harder, trying not go slide down. If he had one of those nook things, Karkat did too... he had to know what it was like to be inside of one of those things.

Karkat finally pulled his mouth off, gasping quietly for breath before he went back for more. He gave up on fingering the former human, sliding his fingers from Dave's nook. He struggled with the zipper of his jeans and shoved the fluid slick fingers into his own nook, uncaring that they were coated with Dave's lime already.

Dave whimpered. Seeing the green pre-cum on Karkat's fingers getting pushed inside of his fiery red nook was so... delicious looking. He took a shuddered breath and licked his lips, a little unsure of how much longer he could last with the way the Cancer's mouth worked on his weird alien tentacle thing. He released Karkat's hair and shifted. "Stand up."

Karkat opened his eyes and looked up at Dave in a mixture of annoyance and surprise. Fuck, he was doing it wrong somehow wasn't he? He grudgingly pulled his fingers free of his nook as he took his mouth off the lime's bulge before doing as Dave said, watching the Strider warily.

Dave kissed Karkat on the mouth, shocked to find that the traces of lime in his mouth actually tasted mildly like a lime Jolly Rancher. He licked over the roof of Karkat's mouth before grunting softly, pushing Karkat to his workstation, bending him over the table. Just as Dave thought, it gave the Strider a perfect view of that gorgeous dripping nook and he pressed one hand to the small of Karkat's back to keep him there while his index and middle fingers traced the lips of that beautiful dribbling mess.

Karkat gasped sharply, not expecting Dave to bend him over the way he did. He growled quietly, shoving his computer away from his face. He moved to push himself up, but Dave was surprisingly stronger than he looked, his hold being unyielding to the cherryblooded troll. "Damnit Strider, the fuck do you -" His words were cut off by his own small shaky moan and he dropped his face to the table, panting lightly.

Dave could feel his own toes curling at the thought of being inside of the tight heat his fingers were currently playing with. He pulled Karkat's jeans down completely around his ankles. This was something he was used to; something he knew. All he had to do was practically mount Karkat and let that dripping nook engulf his bulge, right? Dave grinned into Karkat's skin as he pushed his fingers into the slippery heat, kissing and biting at his neck.

The smaller troll heard himself mewl but he was far past the point of truly caring what he sounded like. He squirmed, trying to buck his hips back to make Dave's fingers go deeper, but the limeblood's weight on his body made that near impossible. He whined, trying to push Dave off him. "Don't fucking tease me!" he snapped, but it sounded more like a plea than the command he intended it to be.

Dave chuckled in Karkat's ear, nipping at the point. He thrust his fingers into the grumpy troll's nook, almost losing his train of thought at the fact of HOW Karkat could be near literally inches from getting laid and still be angry and pissy. It was a fucking anomaly. He pulled his fingers from inside of Karkat, licking the cherry colored substance slightly before just wiping them on his shirt. "Sit fucking still already."

Karkat growled quietly but did as Dave asked, able to still his hips only because there was no longer anything inside him. He felt pre-fluid steadily leak down his thighs and he tried spreading his legs further, only to find then trapped by his jeans.

Dave looked over Karkat's frame, a happy trill leaving his throat. Shuddering, he reached down and grasped his own bulge, feeling the slick length writhe and wiggle in his hand. This alien shit was weird, but everything felt too absolutely amazing for the Strider to care. He moved closer to Karkat, his bulge seemingly knowing exactly what to do. The tip licked at Karkat's folds, causing them both to shudder before he pushed forward a bit, being swallowed by the most delicious heat he could ever fathom.

The crab gave a low mewl, arching his hips and pressing them back to allow for deeper access to his nook. He bit his lip after he did so, however, for when Dave slid in further an almost uncomfortable ache seemed to roll through his nook, informing him that the larger troll was stretching him. He whimpered quietly, panting as he struggled to get used to the strange sensation.

Dave bucked his hips, unable to really stop with the sensations that were wracking his new body. This definitely didn't feel like any human sex he'd ever had... maybe staying a troll wasn't a bad idea. Every nerve ending in his body felt like it was on fire with the sweetest of burns. The limeblood gripped at Karkat's hips, massaging the skin with a moan falling from his lips.

Karkat shivered, his nook clenching around Dave's tentacle as his body quickly adapted to the stretch. His thighs quivered, and he found himself thankful that, despite how humiliating the situation actually was, Dave had bent him over the table. He wasn't so sure he'd be able to hold himself up otherwise. He rocked his hips a bit, his nook becoming unsatisfied with merely being filled. "Come on, shitfuck! Quit being such an asshole and fuck me right!" he growled, unable to remain stationary.

A smirk for it's way to Dave's lips and he was more than happy to oblige. He pushed his hips forward, thrusting hard. He didn't really see the point in being too gentle with the mutant troll if Karkat was just going to keep bossing him around for more. Dave bit Karkat's shoulder and groaned at the way he would quiver underneath the limeblood's form. "Sh-shit, Karkat..." He'd never felt something this tight around his dick or otherwise.

Karkat trilled, digging his claws into the table for leverage to hold his hips up to make sure Dave when as deep as possible. The bulge inside him coiled and flicked nicely against his inner walls, and small mewls left his mouth with every sensation. "Fuck," he gasped at a particularly hard thrust, his nook clamping down tightly on Dave's bulge in reflex.

A groan was pulled from Dave and he gripped at Karkat's hip with one hand while holding onto the table for balance with the other. He whined softly, Karkat's insides felling like they were going to make him melt before long. The delicious heat was too much as he continued to thrust, determined to have Karkat become a weak and quivering mess underneath him.

The Cancer continued to squirm beneath Dave, gasping and purring. He keened loudly when Dave gripped his hip, and he reached up with one hand to tug his shirt up. "Play..nmm... play with my grub scars," he demanded breathlessly.

Dave could only assume that the "grub scars" Karkat demanded be fondled were the bright flushed red ridges lining Karkat's sides. He panted softly as he tried to keep up the rhythm of his thrusts as he focused on those small mounds. The way Karkat was trembling absolutely made it worth it though.

Karkat was soon reduced to keens and trills, his nook throbbing with every thrust. His back arched, the pleasure becoming too much for him, and before too long he found himself crying out, a loud desperate yell as his nook shuddered, tightening around the lime tentabulge inside him.

Dave whimpered from the sudden tightness around his alien cock. He grasped at Karkat's sides, his heel grinding into one of the scars as he tried to keep his balance. The sudden rush of hot release engulfing his bulge was just enough to bring the taller male over the edge. His breath hitched as he pushed deep into Karkat, lime genetic material filling him to the core.

Karkat moaned, long and wavery as his orgasm drew out from the sensations of being filled even further. He bit down on his tongue, almost crying out Dave's name before he caught himself. It felt like ages before he came down from the high, gasping and trembling beneath the midblood still inside him.

The taller male gave a few shallow thrusts as he worked through his own comedown. He pulled free from Karkat, almost stumbling as he fixed his godtier pants. The Knight of Time looked down, trying to not moan at the sight of watching the bright green and red slurry running down his partner's legs. He smirked, smacking the Cancer's ass. "Even fuckin' Sonic would be jealous of that goddamn cherry-limeade runnin' down yer leg there, Karkat."

Karkat blushed hard, his face burning with from the comment. "Who the fuck is Sonic?" He snarled, standing upright to pull his pants up quickly. The movement was almost too much after his first orgasm and he braced himself against the desk as the room swam for a second. He glared at Dave, effectively ruined by the red stained across his cheeks.

Dave laughed softly and kissed Karkat's blush quickly. He wasn't really sure if the action was because it would annoy Karkat or if the troll was just kind of adorable. "It's a...well, was, a badass drive in food place. Those fuckin' tatertots were the shit, bro."

Karkat managed an eyeroll. "More weird human shit," he grumbled, turning even redder from Dave's kiss. He didn't object, though, and after a few seconds he leaned forward and gave Dave's lips a quick kiss in return, before looking back to the floor beneath his work station. "...you're cleaning that up."


End file.
